LIKE RUST SLOWLY consuming the body of a car, drought has spread upstream on the Colorado River.

The river’s Upper Basin – generally north of Lake Powell – has been largely insulated from the 19-year drought afflicting the giant watershed, thanks to the region’s relatively small water demand and heavy snows that bury Colorado’s 14,000ft peaks each winter. But this year, there was no salvation in the snowpack.

Several major Colorado River tributaries – the Dolores, San Juan and Gunnison rivers – saw record-low snowpack this winter. Others, including the Yampa River and the headwaters of the Colorado itself, did not break records but saw snowpack shrink to 70 percent or less of average.

As a result, many reservoirs on the west slope of the Rocky Mountains have shrunk to mud puddles. In August, the resort city of Aspen, Colorado, imposed mandatory watering restrictions on its residents and visitors for the first time in its history. And in another first, the state of Colorado curtailed water rights on the Yampa River – which flows through Steamboat Springs – forcing some water users to stop extracting water to protect higher-priority users and aquatic life in the river.

In the Colorado River’s more arid Lower Basin, the chronic drought has received plenty of attention due to the dramatic shrinkage of Lake Mead and the likelihood of water shortages for Arizona, Nevada and California in 2020. But drought in the Upper Basin has gone relatively unnoticed, and in many ways it will be a much tougher problem to solve.

“This is the first time we’ve had to wake up in the morning and say, ‘Oh my gosh, our lives have changed,’” says Doug Monger, a county commissioner in Routt County, Colorado, home to Steamboat Springs. “It’s scary as hell.”

Mead and Powell are the largest and second-largest reservoirs in the nation, respectively. They’re linked by the Grand Canyon, one of the planet’s most iconic geologic features. Yet while everyone has watched epic drought paint a giant bathtub ring around Lake Mead, Lake Powell has been shrinking, too.

The water elevation at Powell has sunk 94ft since 2000. A big reason is that Lake Powell has been used to keep Lake Mead from sinking to an elevation of 1,075ft, the point at which the federal government must declare a water shortage under a 2007 agreement. This would cause mandatory water delivery cuts to the Lower Basin states, triggering widespread water rationing.

A new report by a team of science and policy experts, known as the Colorado River Research Group, notes that continuing this practice will bring harm to Lake Powell. If the lake shrinks, it could compromise hydropower generation at Glen Canyon Dam and prevent Lake Powell from continuing to backfill Lake Mead.

It could also touch off an ugly dispute between the two basins. To reach agreement on the 1922 Colorado River Compact, Upper Basin states committed to send the Lower Basin states a certain amount of water. As measured at Lee’s Ferry, just below Lake Powell, those water deliveries must achieve a 10-year running average of 75 million acre-feet. If not, the Lower Basin states can declare a “compact call,” triggering negotiations that could subject the Upper Basin states to water rationing.

That prospect, long considered remote, may now be looming.

“The lower Lake Powell gets, the higher the probability that’s going to happen,” says Douglas Kenney, a member of the research group and director of the Western Water Policy Program at University of Colorado Law School. “A compact call would be devastating in the Upper Basin. It would be total chaos.”

That’s because there are no hard and fast rules to govern a compact call. There is no clear trigger for the process, unlike the elevation triggers at Lake Mead. And there is no clear process that follows declaration of a compact call, nor any rules about who should cut their water use.

If the Lower Basin declares a compact call, Kenney says, it would surely be contested by Upper Basin water users.

“Some of that could be Supreme Court-type litigation that could come into play,” he says. “If you get to that point, all you’re doing is saying there’s not going to be enough water for everybody, so let’s decide who’s going to get the short end of the stick. You never solve problems when you get to that situation.”

A general view of Glen Canyon Dam from the Carl Hayden Visitor Center in Glen Canyon National Recreation Area in Lake Powell, Utah, on February 11, 2017. (Photo credit: RHONAWISE/AFP/Getty Images)

Powell has continued shrinking not just because of drought in the Upper Basin, but because the Lower Basin has benefited from surplus water passed through Glen Canyon Dam – beyond requirements of the 1922 agreement. Through interim rules adopted in 2007, surplus flows in the Upper Basin have been passed along to Lake Mead to keep the latter from falling into shortage. This water would have otherwise stayed in Lake Powell and avoided the decline in water elevation there.

This has amounted to an 11 million acre-feet bonus for Lake Mead since the surplus water began flowing, Kenney’s group found in the new report. And Lake Powell is likely to go on shrinking as long as these water releases continue.

In addition to the threat of a compact call, Colorado now has its own water shortages to worry about from drought and climate change. A new study, for instance, blames 53 percent of the decline in water flows in the Colorado River on warmer temperatures, not just less precipitation. This is likely to continue as temperatures warm, a worrisome trend since the Upper Basin delivers about 90 percent of all the flow in the Colorado River.

Meanwhile, Colorado has become one of the nation’s fastest-growing states. It is expected to add 3 million people by 2050, a 56 percent increase. Most of this growth will occur on the Front Range, from Fort Collins to Colorado Springs, a region served by water imported by tunnels through the Rockies from the state’s West Slope.

These water diversions have long been a source of friction for West Slope residents such as Monger, whose family has raised cattle in Routt County for four generations.

“What we want to see is an acknowledgment that there’s no more free water in the Colorado River System,” says Monger, also a board member of the Colorado River Water Conservation District, a West Slope water agency. “There’s no more unallocated water in the Colorado River to be shipping to the Front Range. It’s gotta end.”

Yet Front Range communities are planning to extract even more water from Colorado River tributaries, adding to declines at Lake Powell. There are at least seven major new water storage and diversion projects planned in the state that could divert a total of 400,000 acre-feet annually.

Even so, Monger also wants more water storage on the West Slope. No official proposal exists yet, but he would like to see a new reservoir built to supplement flows in the Yampa River through Steamboat Springs. Otherwise, he fears, summer fly-fishing tourism will dry up.

Gary Wockner, executive director of the conservation group Save the Colorado, says he’ll fight any such proposal. Already, the group has brought legal action against two water storage projects planned for the Front Range.

“There is all sorts of room in all sorts of places to find more efficient uses of water, and more ways to use water which don’t kill the rivers,” Wockner says. “But they won’t do it. They want to drain the rivers first and we’re going to stop them.”

One option, he says, is for the state to invest heavily in cash-for-grass programs to eliminate thirsty urban lawns. This could reduce the need for more water diverted through tunnels to the Front Range. Only Fort Collins has such a program, he says, and it’s small.

Another option is to pay farmers to stop growing crops during drought conditions. The Metropolitan Water District of Southern California has had success with this kind of “rotational fallowing” program, in partnership with farmers who depend on diversions from the Lower Colorado River.

Earlier this year, it was announced that a similar program targeting the Upper Basin is being suspended. Known as the System Conservation Pilot Program, it paid farmers to fallow crops, allowing the saved water to flow downstream to Lake Powell. But over three years, it saved only about 22,000 acre-feet of water at a cost of $4.6 million.

Kenney says the program wasn’t more successful because it wasn’t big enough to attract more farmers. Also, water agencies on the West Slope complained there was no legal mechanism to save the water in Lake Powell for future use by the Upper Basin. Today, any water that reaches Lake Powell is fair game to be sent on to Lake Mead and the Lower Basin states. Instead, they want to see a protected water bank created in Lake Powell to hold the saved water.

The Upper Basin of the Colorado River has begun experiencing water shortages due to a 19-year drought. A new research report says it might be time to stop thinking of the river as two separate basins. (IMAGECREDIT: U.S. Geological Survey)

Kenney says fundamental legal shortcomings need to be addressed on the Colorado River, both to conserve water and to avoid the chaos of a compact call.

One is that Colorado River water users need to stop thinking of the watershed as two separate basins. This is an artificial construct that divides water users and stands in the way of solutions, he says.

In its new report, Kenney’s group stops short of endorsing a controversial “Fill Mead First” concept, in which the primary aim is to restore Glen Canyon, possibly including breaching the dam. But he does say it is time to start thinking of Powell and Mead as one giant reservoir, rather than separate pools in isolation.

This would take major changes in law and policy. But Kenney says the likelihood of continued water shortages due to climate change makes this a goal worth pursuing. The law of the river that has guided the Colorado thus far, he says, simply isn’t adequate for the challenges now facing the watershed and its people.

“If we didn’t have all these rules etched in stone, could we actually make this water go further?” Kenney asks. “If we could just think a little more broadly, open our eyes to a greater realm of possibilities, maybe we could arrive at a better solution.”

As originally published in Water Deeply by Matt Weisner on September 11, 2018